In the technology evolvement from the current to the next generation network (Next Generation Network, NGN for short), interconnection of multi-media information, such as voice, video and even a short message on a traditional telephone switched network, such as a network protocol (Internet Protocol, IP for short) packet network and a public switched telephone network (PSTN for short) may be realized through various means, such as soft switch, multimedia subsystem (IP Multimedia Core Network Subsystem, IMS for short), H.323 and session initiation protocol (SIP for short) server. The tendency of replacing time division multiplex (TDM for short) with an IP has established and has been widely applied. Comparing with a traditional circuit-based voice technology, Voice over IP (VoIP for short) is not only cheap, but voice quality also has been improved significantly with the increase of bandwidth. More importantly, various multimedia applications based on IP make VoIP have a strong appeal.
On the other hand, the progress of broadband technology changes rapidly in recent years. From the aspect of the wire aspect, the progress is from an asymmetric digital subscriber line (ADSL for short) to a video digital subscriber line (VDSL for short) and then to a passive optical network of various degrees (PON for short). From the aspect of the wireless aspect, the progress is from a general packet radio service (GPRS for short) to high-speed packet data access (HSPDA for short), to worldwide interoperability for microwave access (WiMAX for short), and to long-term evolution (LTE for short). At present, with the mature of wireless fidelity (WiFi for short) technology and the large deployment of WiFi access point (AP for short), family/enterprise/hotspot area may access the Internet free or with preferences, and enjoy a higher network speed.
Numerous Internet service providers (ISP for short) develop various soft terminals to provide customers with services of instant messaging (IM), PRESENCE and VoIP, such as MSN and Skype. Certain clients supporting social services, such as IM and PRESENCE can associate multiple user numbers of a user simultaneously, such as a mobile number and a fixed number, and when the user is called, ringing may be performed simultaneously or in a sequence so as to finish connection. However, as regards ringing in a sequence, connection time would be very long in an extreme case and influence the feeling of a calling side customer. At the same time, since a called number is not certain, cost may be different; moreover, a VoIP client at the calling side cannot learn a called number bound by a called party; therefore, the calling side user may not learn which called number (mobile or fixed number) is connected at last, thereby influencing the financial feeling of the calling side. Finally, for the operator, no matter simultaneously ringing or ringing in a sequence, a call attempt mode is adopted to perform connection, thereby occupying a large amount of call attempt resources, and the more numbers bound by the called user, the more resources occupied by the call attempt, and the more waste caused. Moreover, since the VoIP client on the calling side may not learn a called number currently bound by a called party, a calling user does not have the right of selecting a number to be finally connected.
For the problem of terrible user experience in traditional art caused by the VoIP client on the calling side failing to learn a called number currently bound by a called party, no effective solution has been proposed at present.